JP2013097229A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projector which can be started at a high speed while suppressing local heat generation of phosphors.SOLUTION: A projector 1 comprises: a light source device 55 including at least an excitation light source 11 for emitting excitation light; a fluorescent light circular plate 13 on which phosphors for converting the excitation light into fluorescent light are continuously formed along a circumferential direction; a motor section 14 for rotating the fluorescent light circular plate 13 about an axis passing through the center of a circle thereof in a circumferential direction; light modulators 30R, 30G and 30B which modulate light including at least the fluorescent light and generate image light; and a projection optical system 60 for projecting the image light. When a number of revolutions of the fluorescent light circular plate 13 attains a predetermined number of revolutions lower than a target value, the excitation light source 11 is lit. After the number of revolutions of the fluorescent light circular plate 13 has attained the predetermined number of revolutions, an output of the excitation light source 11 is increased when the number of revolutions of the fluorescent light circular plate 13 is increased.

Description

  The present invention relates to a projector.

  2. Description of the Related Art Conventionally, projectors having features such as small size, low power consumption, and long life have been proposed by using a solid light source such as an LED (light emitting diode) or an LD (laser diode) as a light source device. In addition, there is a projector that attempts to realize the above-described features by including a light source device that combines a solid light source and a phosphor (see, for example, Patent Document 1).

JP 2011-128340 A

  By the way, since the phosphors described above have problems such as reduction in conversion efficiency or long-term reliability due to heat generation, a technique for preventing local heat generation by rotating the phosphors is also known.

  However, when the structure for rotating the phosphor as described above is adopted, it takes time for the phosphor to reach the desired number of rotations, so the time until the solid light source is turned on, that is, the time for starting the projector. Cost.

  The present invention has been made in view of such circumstances, and provides a projector capable of high-speed startup while ensuring long-term reliability by suppressing local heat generation of a phosphor. Objective.

  In order to solve the above problems, a projector according to the present invention includes a light source device including at least an excitation light source that emits excitation light, and a phosphor that converts the excitation light into fluorescence continuously formed along a circumferential direction. A fluorescent disk, a motor unit that rotates the fluorescent disk in the circumferential direction around an axis that passes through the center of a circle, and a light modulator that modulates light including at least the fluorescence to generate image light, A projection optical system for projecting the image light, and when the rotation speed of the fluorescent disk reaches a predetermined number lower than a target number, the excitation light source is turned on, and the rotation speed of the fluorescent disk is the predetermined number When the number of rotations of the fluorescent disk increases after reaching, the output of the excitation light source increases.

According to the projector of the present invention, the solid state light source is turned on at the timing when the rotation speed of the fluorescent disk reaches a predetermined number lower than the target number at the start of driving of the light source device. Can reduce the time to wait for the user to start up. In addition, since the output of the solid light source increases in accordance with the increase in the rotation speed of the fluorescent disk after the solid light source is turned on, the light amount of the solid light source is suppressed when the rotation speed of the fluorescent disk is low. Yes. Therefore, deterioration of the phosphor can be suppressed by irradiating the high-output excitation light onto the fluorescent disk having a low rotational speed.
Therefore, it is possible to provide a projector that realizes high-speed startup while ensuring the long-term reliability of the phosphor.

In the projector, it is preferable that the output of the control unit increases due to an increase in input power to the excitation light source.
According to this configuration, it is possible to simply and reliably increase the output of the solid state light source by increasing the input power.

Further, in the projector, the excitation light source of the excitation light source is based on a lookup table in which a relationship between an elapsed time after the rotation number of the fluorescent disk reaches a predetermined number and a rotation number of the fluorescent disk is set in advance. The output is preferably increased.
According to this configuration, it is possible to easily obtain the rotational speed of the fluorescent disk based on the elapsed time after the rotational speed of the fluorescent disk reaches a predetermined number by using a preset lookup table. it can.

In the projector, it is preferable that the rotation speed of the fluorescent disk is detected from the motor unit, and the output of the excitation light source is increased according to the detection result.
According to this configuration, since the rotation speed of the fluorescent disk can be acquired from the motor unit as needed, output control of the solid light source can be performed with high accuracy.

In the projector, the timing at which the rotation speed of the fluorescent disk reaches the target number is earlier than or substantially equal to the timing at which the input power to the excitation light source reaches the target value. preferable.
According to this configuration, the timing at which the rotation speed of the fluorescent disk is saturated is earlier than or substantially equal to the timing at which the input power to the solid light source is saturated, so that fluorescence can be stably generated.

In the projector, it is preferable that the excitation light source is driven by pulse driving, and the drive frequency of the excitation light source is not less than three times the frequency of the fluorescent disk and a non-integer multiple.
According to this configuration, it is possible to prevent the occurrence of flicker due to interference between the driving frequencies of the solid light source and the fluorescent disk.

In the projector, it is preferable that the light source device includes a solid light source that emits light that forms white light together with the fluorescence, and the excitation light source is turned on and the solid light source is turned on.
According to this configuration, since the drive of the light source device is controlled so as to maintain the white balance by the control unit, it is possible to provide a highly reliable projector that can obtain bright and clear image light.

FIG. 1 is a schematic diagram schematically illustrating an overall configuration of a projector according to a first embodiment. FIG. 3 is a diagram illustrating a configuration of a rotating fluorescent screen provided in the projector according to the first embodiment. FIG. 2 is a block diagram illustrating a main configuration of a control system of the projector according to the first embodiment. 6 is a flowchart illustrating a processing procedure of a control system of the projector according to the first embodiment. The figure which shows the input electric power to the light source drive part in 1st Embodiment. The block diagram which shows the principal part structure of the control system of the projector which concerns on 2nd Embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. Such embodiment shows one mode of the present invention, does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. Moreover, in the following drawings, in order to make each structure easy to understand, the scale, number, etc. in the actual structure are different.

(First embodiment)
FIG. 1 is a schematic diagram schematically illustrating the overall configuration of the projector according to the first embodiment.
As shown in FIG. 1, the projector 1 includes an illumination device 10, a color separation light guide optical system 20, liquid crystal light modulation devices 30 R, 30 G, and 30 B (light modulation devices), a cross dichroic prism 40, and a projection optical system 60. An image is displayed on the screen SCR by projecting image light according to an image signal input from the outside toward the screen SCR.

  The illumination device 10 includes a light source device 55 including a first light source (excitation light source) 11 and a second light source (solid light source) 50, condenser lenses 12 and 51, a rotating fluorescent plate (fluorescent disk) 13, and a motor (motor unit) 14. , A diffusion plate 52, collimator optical systems 15 and 53, a beam splitter 54, a first lens array 16, a second lens array 17, a polarization conversion element 18, and a superimposing lens 19.

  As the first light source 11 and the second light source 50, for example, a semiconductor laser array including a plurality of semiconductor laser elements in which a single semiconductor laser element is arranged in a planar shape can be used. In this way, high output blue light can be obtained by using a device including a plurality of semiconductor laser elements. Further, the first light source 11 and the second light source 50 will be described by taking as an example one emitting blue light having an emission intensity peak of 445 nm. However, an emission intensity peak different from this (for example, about 460 nm) is described. What has can also be used.

  The condensing lens 12 is disposed on the optical path between the first light source 11 and the rotating fluorescent plate 13 and condenses the blue light emitted from the first light source 11 at a position near the rotating fluorescent plate 13. It is.

  The rotating fluorescent plate 13 converts blue light as excitation light collected by the condenser lens 12 into yellow light (fluorescence) including red light and green light, and is rotatably supported by a motor 14. Yes.

  2A and 2B are diagrams showing a configuration of the rotating fluorescent screen 13 provided in the projector according to the present embodiment, in which FIG. 2A is a front view, and FIG. 2B is a cross-sectional arrow along the line AA in FIG. FIG. As shown in FIG. 2, the rotating fluorescent plate 13 is formed by continuously forming a phosphor 13b as a single fluorescent layer on one surface of a transparent disc 13a along the circumferential direction of the disc 13a. is there.

The circular plate 13a is formed using a material that transmits blue light, such as quartz glass, crystal, sapphire, optical glass, and transparent resin. A hole through which the rotation shaft of the motor 14 is inserted is formed at the center of the disk 13a. The phosphor 13b allows the blue light from the first light source 11 to pass through in a state converted into yellow light (fluorescence) including red light and green light. As the phosphor 13b, for example, a YAG-based phosphor _{(Y, Gd) 3 (Al} , Ga) 5 O 12: it is possible to use those containing Ce. As shown in FIG. 2B, the phosphor 13b is formed on one surface of the disk 13a via a dichroic film 13c that transmits blue light and reflects red light and green light.

  The rotating fluorescent plate 13 faces the surface on which the phosphor 13b is formed to the side opposite to the side on which the blue light is incident so that the blue light from the first light source 11 enters the phosphor 13b from the disc 13a side. Arranged. The rotating fluorescent plate 13 is arranged near the condensing position of the condensing lens 12 so that blue light is always incident on the region where the phosphor 13b is formed while being driven by the motor 14 and rotating. Established.

  The rotating fluorescent plate 13 is rotationally driven by the motor 14 at, for example, 5000 rpm in a steady state. Here, the diameter of the rotating fluorescent plate 13 is 50 mm, and the incident position of the blue light collected by the condenser lens 12 with respect to the rotating fluorescent plate 13 is set at a position about 22.5 mm away from the rotational center of the rotating fluorescent plate 13. ing. That is, the rotating fluorescent plate 13 is rotationally driven by the motor 14 at such a rotational speed that the focused spot of blue light moves on the phosphor 13b at about 12 m / sec.

  Returning to FIG. 1, the collimator optical system 15 includes a first lens 15 a and a second lens 15 b, and makes the light from the rotating fluorescent plate 13 substantially parallel. The condensing lens 51 is disposed on the optical path between the second light source 50 and the diffusion plate 52 and condenses the blue light emitted from the second light source 50 at a position near the diffusion plate 52. The blue light diffused by the diffusion plate 52 is approximately collimated by the collimator optical system 53. The collimator optical system 53 includes a first lens 53a and a second lens 53b.

  The beam splitter 54 reflects the blue light emitted from the second light source 50 while transmitting the fluorescence generated by the rotating fluorescent plate 13. Thereby, the fluorescence via the rotating fluorescent plate 13 and the blue light emitted from the second light source 50 are combined to generate white light including red light, green light, and blue light. This white light is incident on the first lens array 16.

  The first lens array 16 has a plurality of small lenses 16a, and divides the white light into a plurality of partial light beams. Specifically, the plurality of small lenses 16a included in the first lens array 16 are arranged in a matrix over a plurality of rows and a plurality of columns in a plane orthogonal to the illumination optical axis AX. The outer shape of the plurality of small lenses 16a included in the first lens array 16 is substantially similar to the outer shape of the image forming area of the liquid crystal light modulation devices 30R, 30G, and 30B.

  The second lens array 17 has a plurality of small lenses 17 a corresponding to the plurality of small lenses 16 a provided in the first lens array 16. That is, the plurality of small lenses 17a included in the second lens array 17 extends over a plurality of rows and columns within a plane orthogonal to the illumination optical axis AX, similarly to the plurality of small lenses 16a included in the first lens array 16. Arranged in a matrix. The second lens array 17 forms an image of each small lens 16a included in the first lens array 16 together with the superimposing lens 19 in the vicinity of the image forming regions of the liquid crystal light modulation devices 30R, 30G, and 30B.

  The polarization conversion element 18 includes a polarization separation layer, a reflection layer, and a retardation plate (all not shown), and the polarization direction of each partial light beam divided by the first lens array 16 is aligned with the polarization direction. It is emitted as almost one type of linearly polarized light. Here, the polarization separation layer transmits one linearly polarized light component included in the white light as it is, and reflects the other linearly polarized light component in a direction perpendicular to the illumination optical axis AX. The reflective layer reflects the other linearly polarized light component reflected by the polarization separation layer in a direction parallel to the illumination optical axis AX. Furthermore, the phase difference plate converts the other linearly polarized light component reflected by the reflective layer into one linearly polarized light component.

  The superimposing lens 19 is arranged so that the optical axis thereof coincides with the optical axis of the illumination device 10, and condenses each partial light beam from the polarization conversion element 18, and images of the liquid crystal light modulation devices 30R, 30G, and 30B. Superimpose near the formation area. The first lens array 16, the second lens array 17, and the superimposing lens 19 described above constitute a lens integrator optical system that uniformizes the light from the first light source 11.

  The color separation light guide optical system 20 includes dichroic mirrors 21 and 22, reflection mirrors 23 to 25, relay lenses 26 and 27, and condensing lenses 28R, 28G, and 28B, and converts the light from the illumination device 10 into red light. , Green light and blue light are separated and guided to the liquid crystal light modulation devices 30R, 30G and 30B, respectively. The dichroic mirrors 21 and 22 are mirrors in which a wavelength selective transmission film that reflects light in a predetermined wavelength region and transmits light in other wavelength regions is formed on a transparent substrate. Specifically, the dichroic mirror 21 passes a red light component and reflects green light and blue light components, and the dichroic mirror 22 reflects a green light component and passes blue light components.

  The reflection mirror 23 is a mirror that reflects a red light component, and the reflection mirrors 24 and 25 are mirrors that reflect a blue light component. The relay lens 26 is disposed between the dichroic mirror 22 and the reflection mirror 24, and the relay lens 27 is disposed between the reflection mirror 24 and the reflection mirror 25. These relay lenses 26 and 27 are provided in order to prevent a decrease in light use efficiency due to light divergence and the like because the length of the optical path of blue light is longer than the length of the optical paths of other color lights. The condensing lenses 28R, 28G, and 28B convert the red light component reflected by the reflection mirror 23, the green light component reflected by the dichroic mirror 22, and the blue light component reflected by the reflection mirror 25 into the liquid crystal light modulation device 30R. , 30G, and 30B, respectively.

  The red light that has passed through the dichroic mirror 21 is reflected by the reflecting mirror 23 and enters the image forming area of the liquid crystal light modulation device 30R for red light through the condenser lens 28R. The green light reflected by the dichroic mirror 21 is reflected by the dichroic mirror 22 and enters the image forming region of the liquid crystal light modulation device 30G for green light via the condenser lens 28G. The blue light reflected by the dichroic mirror 21 and passing through the dichroic mirror 22 passes through the relay lens 26, the reflection mirror 24, the relay lens 27, the reflection mirror 25, and the condenser lens 28B in this order, and the liquid crystal light modulation device 30B for blue light. Incident on the image forming area.

  The liquid crystal light modulation devices 30R, 30G, and 30B modulate incident color light according to an image signal input from the outside, and generate red image light, green image light, and blue image light, respectively. Although not shown in FIG. 1, incident-side polarizing plates are interposed between the condenser lenses 28R, 28G, 28B and the liquid crystal light modulators 30R, 30G, 30B, respectively. Between the modulation devices 30R, 30G, and 30B and the cross dichroic prism 40, an exit side polarizing plate is interposed.

  The liquid crystal light modulators 30R, 30G, and 30B are transmissive liquid crystal light modulators in which a liquid crystal that is an electro-optical material is hermetically sealed between a pair of transparent glass substrates. For example, a polysilicon TFT (Thin Film Transistor: A thin film transistor) as a switching element. By modulating the polarization direction of the color light (linearly polarized light) through each of the incident side polarizing plates (not shown) described above by the switching operation of the switching elements provided in each of the liquid crystal light modulation devices 30R, 30G, and 30B. Then, red image light, green image light, and blue image light corresponding to the image signal are respectively generated.

  The cross dichroic prism 40 synthesizes the image light emitted from each of the above-described exit side polarizing plates (not shown) to form a color image. Specifically, the cross dichroic prism 40 is a substantially cubic optical member formed by bonding four right-angle prisms, and a dielectric multilayer film is formed at a substantially X-shaped interface where the right-angle prisms are bonded together. Has been. The dielectric multilayer film formed at one of the substantially X-shaped interfaces reflects red light, and the dielectric multilayer film formed at the other interface reflects blue light. By these dielectric multilayer films, the red light and the blue light are bent and aligned with the traveling direction of the green light, so that the three color lights are synthesized. The projection optical system 50 enlarges and projects the color image synthesized by the cross dichroic prism 40 toward the screen SCR.

  Next, the operation of the projector 1 will be described. FIG. 3 is a block diagram showing the main configuration of the control system of the projector 1 according to the present embodiment. In FIG. 3, only members necessary for explanation are extracted from the members illustrated in FIG. 1 and are illustrated in a simplified manner.

  As shown in FIG. 3, the projector 1 includes a control unit 61, a light source driving unit 62, a motor driving unit 63, and a light modulation device driving unit 64. The light source driver 62 includes a first light source driver 62 a that drives the first light source 11 and a second light source driver 62 b that drives the second light source 50.

  The control unit 61 is realized by including a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory) (all of which are not shown). The CPU reads the control program stored in the ROM, expands it in the RAM, and executes the program steps on the RAM. The control unit 61 controls the overall operation of the projector 1 by executing the program by the CPU.

  The control unit 61 includes a drive current setting unit 101 and a signal processing unit 102.

  The drive current setting unit 101 generates a signal for setting the drive current of the first light source 11 and the second light source 50 (hereinafter referred to as a drive current setting signal), and the light source drive unit 62 (first light source drive unit 62a). And the second light source driving unit 62b). The first light source driver 62 a drives the first light source 11 based on the drive current setting signal, and emits blue light from the first light source 11. The second light source driving unit 62b drives the second light source 50 based on the driving current setting signal, and emits blue light from the second light source 50. In this way, the drive current setting unit 101 controls the input power to the first light source 11 and the second light source 50 by controlling the drive current setting signal supplied to the light source drive unit 62, and the first light source 11 and the first light source 11 The output (light quantity) of blue light emitted from each of the two light sources 50 is controlled.

  The signal processing unit 102 supplies a rotation control signal for rotating the motor 14 to the motor driving unit 63. Further, the signal processing unit 102 detects the actual number of rotations of the motor 14 (the rotating fluorescent plate 13) based on the rotation detection signal of the motor 14 supplied from the motor driving unit 63. Further, the signal processing unit 102 supplies a rotation speed detection signal of the detected rotation speed of the motor 14 to the drive current setting unit 101. Accordingly, the drive current setting unit 101 controls the input power to the first light source 11 and the second light source 50 according to the number of rotations of the motor 14 (rotary fluorescent screen 13), and controls the output of these light sources.

The signal processing unit 102 receives a video signal from an external device such as a computer, a DVD player, or a TV tuner. The signal processing unit 102 performs image resizing, gamma adjustment, color adjustment, and the like by, for example, video signal characteristic correction and amplification, and decomposes the video signal into R, G, and B video data. The signal processing unit 102 generates a light modulation signal for driving the liquid crystal light modulation devices 30R, 30G, and 30B (light modulation devices) for each color light, and transmits the light modulation signal to the light modulation device drive unit 64.
The light modulation device driving unit 64 drives the liquid crystal light modulation devices 30R, 30G, and 30B based on the light modulation signal transmitted from the signal processing unit 102. Specifically, the light modulation device drive unit 64 drives the liquid crystal light modulation device 30R for red light according to the light modulation signal for red, and the liquid crystal light modulation device for green light according to the light modulation signal for green light. 30G is driven, and the blue light liquid crystal light modulation device 30B is driven in accordance with the blue light modulation signal.

  Next, control of the projector 1 described above will be described. FIG. 4 is a flowchart showing the processing procedure of the control system of the projector 1 according to this embodiment, and shows the processing procedure when the projector 1 is activated.

  When the power supply of the projector 1 is turned on (step S1), the signal processing unit 102 of the control unit 61 supplies a rotation control signal to the motor driving unit 63 (step S2). As a result, the rotating fluorescent plate 13 starts rotating as the motor driving unit 63 drives the motor 14.

  The signal processing unit 102 detects the number of rotations of the motor 14 based on the rotation detection signal supplied from the motor driving unit 63 (step S3), and determines whether or not the number of rotations of the motor 14 has reached a predetermined number. (Step S4). The number of revolutions is detected until the number of revolutions of the motor 14 reaches a predetermined number.

  The predetermined number of rotations of the motor 14 is, for example, 1000 rpm. This predetermined number is a rotational speed lower than 5000 rpm which is the target number of the rotational speed of the motor 14. The target number of rotations is the number of rotations of the rotating fluorescent screen 13 (motor 14) when the driving of the illumination device 10 is stabilized.

  When the signal processing unit 102 detects that the rotation number of the motor 14 has reached a predetermined number (in the case of Yes), the control unit 61 supplies a rotation number detection signal to the drive current setting unit 101. The drive current setting unit 101 sends the drive current setting signals of the first light source 11 and the second light source 50 to the light source drive unit 62 (first light source drive unit 62a and second light source drive unit 62b) based on the rotation speed detection signal. Supply. The first light source driving unit 62a drives the first light source 11 with a predetermined input power lower than the target input power based on the drive current setting signal, and turns on the first light source 11 with a predetermined output lower than the target output. (Step S5). The rotational speed of the motor 14 increases toward the target number even after reaching the predetermined number.

  The target output is, for example, a light quantity of 3000 lm (target value of output) obtained when a target input power (target value of input power) of 1.2 A is supplied to the first light source 11. The target output is the output of the first light source 11 when the driving of the lighting device 10 is stabilized.

  The predetermined output is, for example, a light amount of 800 lm (predetermined value of output) obtained when a current of 0.8 A is applied to the first light source 11 with a predetermined input power (predetermined value of input power).

Subsequently, the control unit 61 determines whether or not the input power to the first light source 11 has reached the target value (step S6). When the input power to the first light source 11 has reached the target value (in the case of Yes), the processing procedure when starting up the projector 1 is ended.
Note that after the processing procedure is completed, the motor 14 rotates at 5000 rmp, which is the target number of rotations, and the first light source 11 outputs 3000 lm, which is the target value of output (light quantity).

  On the other hand, when the input power to the first light source 11 has not reached the target value (in the case of No), the control unit 61 determines whether a predetermined time has elapsed since the rotation number of the rotating fluorescent plate 13 has reached the predetermined number. It is determined whether or not (step S7). When it is determined that the predetermined time has elapsed (in the case of Yes), the control unit 61 increases the input power to the first light source 11 (step S8).

  The determination whether or not the predetermined time has passed (step S7) and the increase in input power (step S8) are repeated until it is determined that the input power to the first light source 11 has reached the target value (step S6).

  In the following description, an increase in input power (step S8) in the first light source 11 will be described.

  In the present embodiment, the output of the first light source 11 is increased using a lookup table calculated in advance. This look-up table is created by evaluating in advance the relationship between the elapsed time after the rotational speed of the rotating fluorescent plate reaches a predetermined number and the rotational speed of the rotating fluorescent screen 13 (motor 14). . Therefore, the control unit 61 refers to the lookup table, and acquires information regarding the rotational speed of the rotating fluorescent plate 13 corresponding to the elapsed time after the rotational speed of the rotating fluorescent plate 13 reaches a predetermined number. If the lookup table is used, the controller 61 does not always have to manage the rotational speed of the rotating fluorescent plate 13 (motor 14), and it is only necessary to manage the time when the rotational speed of the rotating fluorescent plate 13 reaches a predetermined number. The control of the control unit 61 after the first light source 1 is turned on can be simplified.

  The controller 61 increases the input power to the first light source 11 in correspondence with the rotation speed acquired from the lookup table in step S8. Specifically, the drive current setting unit 101 supplies a drive current setting signal for the first light source 11 to the light source drive unit 62. Thereby, the 1st light source drive part 62a increases the output of blue light by increasing the input electric power to the 1st light source 11 based on a drive current setting signal.

FIG. 5 is a diagram illustrating input power to the light source driving unit in the first embodiment.
The controller 61 preferably increases the output (light quantity) of the first light source 11 so as to maintain the rate of change within 2% per unit time (15 to 30 ms). In this way, the brightness of the first light source 11 can be changed smoothly, and the deterioration of the display image quality due to flickering can be prevented. For example, the control unit 61 controls the input power to the first light source 11 so as to increase linearly as shown in FIG. Further, the control unit 61 controls the electric power supplied to the first light source 11 so as to protrude downward as shown in FIG.

  Alternatively, it is conceivable to consider the amount of heat exhausted from the first light source 11 when increasing the output (light quantity) of the first light source 11. When the amount of exhaust heat from the first light source 11 increases, the conversion efficiency of the phosphor 13b is lowered. Therefore, the input power to the first light source 11 is controlled to be convex upward as shown in FIG.

  The control unit 61 controls the first light source 11 so that the timing at which the rotational speed of the rotating fluorescent plate 13 reaches the target number is earlier than or substantially equal to the timing at which the output of the first light source 11 reaches the target value. To do. As a result, the output of the first light source 11 reaches the target value in a state where the rotating fluorescent plate 13 is stably rotated by the target number, so that yellow light is stably incident on the phosphor 13b of the rotating fluorescent plate 13. Light can be generated efficiently.

  According to the present embodiment, the first light source 11 and the second light source 50 are turned on when the rotational speed of the motor 14 that rotates the rotating fluorescent plate 13 reaches 1000 rpm, which is a predetermined rotational speed lower than the target rotational speed of 5000 rpm. By lighting up, it is possible to display an image quickly. Therefore, it is possible to prevent the occurrence of a problem such that the image is not displayed and the user waits for a long time until the rotation speed of the motor 14 reaches the target number.

  According to the present embodiment, after the first light source 11 is turned on, the output of the first light source 11 increases as the rotational speed of the rotary fluorescent plate 13 increases. Thereby, it is possible to suppress the heat generation of the phosphor 13b due to the irradiation of the excitation light having a high output to the rotating fluorescent plate 13 having a low rotation speed, and it is possible to prevent a problem such as a decrease in the conversion efficiency of the phosphor 13b. . Furthermore, the lifetime of the phosphor 13b can be extended by suppressing the heat generation of the phosphor 13b, and the long-term reliability of the phosphor 13b can be ensured.

In the present embodiment, the case where the first light source 11 is turned on in step S5 and the input power to the first light source 11 is increased in step S8 has been described.
However, in step S <b> 5, the second light source driving unit 62 b may turn on the second light source 50 as the first light source 11 is turned on. As a result, white light is incident on the first lens array 16, and the lighting device 10 can emit white light with a good white balance immediately after the lighting device 10 starts driving after the projector 1 is driven. .
In step S8, the input power to the first light source 11 may be increased, and the input power to the second light source 50 may be increased in the same manner. The controller 61 increases the input power to the second light source 50 so as to maintain the white balance of the white light.

  In the present embodiment, the case where the rotation speed of the motor 14 is acquired using a look-up table has been described. However, the control unit 61 can also be connected to the motor 14 via the signal processing unit 102 even after the first light source 11 is turned on. May be acquired in real time, and the input power to the first light source 11 may be increased in accordance with the rotation number. This is particularly effective when there is a difference between the rotational speed acquired from the lookup table and the actual rotational speed of the motor 14 due to changes over time and solid variations.

  In the present embodiment, the timing at which the rotational speed of the rotating fluorescent plate 13 reaches the target number has been described as being a timing earlier or substantially equal to the timing at which the output of the first light source 11 reaches the target value. The control unit 61 may adjust the timing at which the output of the first light source 11 is increased by controlling the rotation of the motor 14.

(Second Embodiment)
Hereinafter, the projector according to the second embodiment will be described. The difference between the present embodiment and the first embodiment is the configuration of the control system of the projector 1. Specifically, in the present embodiment, the first light source 11 and the second light source 50 are pulse-driven, and the outputs of the first light source 11 and the second light source 50 are controlled by controlling the duty of the pulse width modulation. Is different from the first embodiment. Since other configurations are the same as those of the first embodiment, the same members and configurations are denoted by the same reference numerals, and detailed descriptions thereof are omitted or simplified.

  FIG. 6 is a block diagram showing a main configuration of the control system of the projector 1 according to the present embodiment. In FIG. 6, only members necessary for explanation are extracted and simplified from the respective members.

  As shown in FIG. 6, the projector 1 includes a control unit 61, a light source driving unit 62, a motor driving unit 63, and a light modulation device driving unit 64. The light source driver 62 includes a first light source driver 62 a that drives the first light source 11 and a second light source driver 62 b that drives the second light source 50.

  The control unit 61 according to the present embodiment includes a signal processing unit 200 and a PWM signal generation unit 201.

  The signal processing unit 200 takes in the rotation detection signal of the motor 14 supplied from the motor driving unit 63, and detects the number of rotations of the motor 14 (the rotating fluorescent plate 13) based on the rotation detection signal.

  The PWM signal generation unit 201 obtains information on the duty (duty) in the first light source 11 and the second light source 50 driven by pulse width modulation so as to obtain a light amount according to the rotation speed of the motor 14 (hereinafter referred to as duty information and And the duty information is supplied to the light source drive unit 62. The light source driving unit 62 (first light source driving unit 62a and second light source driving unit 62b) drives the first light source 11 and the second light source 50 based on the duty information, and emits blue light from each.

The signal processing unit 200 receives a video signal from an external device such as a computer, a DVD player, or a TV tuner. The signal processing unit 200 performs image resizing, gamma adjustment, color adjustment, and the like by, for example, characteristic correction and amplification of the video signal, and decomposes the video signal into R, G, and B video data. The signal processing unit 200 generates a light modulation signal for driving the liquid crystal light modulation devices 30R, 30G, and 30B (light modulation devices) for each color light, and transmits the light modulation signal to the light modulation device drive unit 64.
The light modulation device driving unit 64 drives the liquid crystal light modulation devices 30R, 30G, and 30B based on the light modulation signal transmitted from the signal processing unit 200. Specifically, the light modulation device drive unit 64 drives the liquid crystal light modulation device 30R for red light according to the light modulation signal for red, and the liquid crystal light modulation device for green light according to the light modulation signal for green light. 30G is driven, and the blue light liquid crystal light modulation device 30B is driven in accordance with the blue light modulation signal.

  Note that the signal processing unit 200 sets the driving frequency of the first light source 11 and the second light source 50 to an integral multiple of the driving frequency of the light modulation device driving unit 64. Thereby, the generation of noise due to interference between the blue light intermittently emitted from the first light source 11 and the second light source 50 and the light modulation operation intermittently performed by the liquid crystal light modulation devices 30R, 30G, and 30B. Is preventing.

  Further, the signal processing unit 200 supplies a rotation control signal for rotating the motor 14 to the motor driving unit 63 to the motor driving unit 63 and takes in a rotation detection signal of the motor 14 supplied from the motor driving unit 63, Based on the rotation detection signal, the actual number of rotations of the motor 14 (the rotating fluorescent screen 13) is detected. Thereby, the signal processing unit 200 has a duty of a signal supplied from the light source driving unit 62 to the first light source 11 and the second light source 50 that are pulse-driven in accordance with the number of rotations of the motor 14 (the rotating fluorescent plate 13). By controlling (Duty), the outputs of the first light source 11 and the second light source 50 are controlled.

  The signal processing unit 200 drives the first light source 11 and the motor 14 so that the driving frequency of the first light source 11 is three times or more the rotational frequency of the motor 14 and satisfies a non-integer multiple relationship. . According to this, flicker generated due to interference between the blue light intermittently emitted from the first light source 11 by pulse driving and the rotation period of the rotating fluorescent plate 13 rotated by the motor 14 can be made inconspicuous, For example, a particularly remarkable effect can be obtained when the amount of light fluctuation increases due to the rotation of the rotating fluorescent plate 13 caused by the solid variation of the phosphor 13b.

  The control unit 61 increases the output of the blue light emitted from the first light source 11 by increasing the duty of the pulse signal input to the light source driving unit 62 by the PWM signal generation unit 201, that is, the amount of light per unit time. Can be increased.

  According to the present embodiment, the output of the first light source 11 can be increased by increasing the duty of the first light source 11 that is pulse-driven by the control unit 61. Therefore, as in the first embodiment, after the first light source 11 is turned on, the output of the first light source 11 is increased as the rotational speed of the rotating fluorescent plate 13 increases. Thereby, the local heat_generation | fever of the fluorescent substance 13b can be suppressed, and the projector which enabled high-speed starting can be provided, ensuring the long-term reliability of the fluorescent substance 13b.

(Modification)
In addition, this invention is not limited to the said embodiment, In the range which does not deviate from the meaning of this invention, it can change suitably. For example, the following modifications are possible.
In the above embodiment, the case of initial driving of the light source device at the start of projector startup has been described. The present invention can be used.

  In the above embodiment, an example in which a liquid crystal light modulation device is used as the light modulation device has been described, but the present invention is not limited to this. In general, the light modulation device only needs to modulate incident light in accordance with an image signal, and a light valve, a micromirror light modulation device, or the like may be used. As the micromirror light modulator, for example, DMD (digital micromirror device) (trademark of TI), LCOS (Liquid Crystal On Silicon), or the like can be used.

  In the above embodiment, the configuration including the solid light source 11 that emits blue light as excitation light and the rotating fluorescent plate 13 that converts the blue light from the solid light source 11 into red light and green light has been described. It is not limited to this. For example, a configuration including a solid light source that emits purple light or ultraviolet light as excitation light and a rotating fluorescent plate that generates color light including red light, green light, and blue light from purple light or ultraviolet light may be used.

  In the above embodiment, a transmissive projector has been described as an example of the projector, but the present invention is not limited to this. For example, the present invention can be applied to a reflection type projector. Here, “transmission type” means that the light modulation device transmits light, such as a transmission type liquid crystal display device, and “reflection type” means a reflection type liquid crystal display device or the like. This means that the light modulation device reflects light. Even when the present invention is applied to a reflective projector, the same effect as that of a transmissive projector can be obtained.

DESCRIPTION OF SYMBOLS 1 ... Projector, 10 ... Illuminating device, 11 ... 1st light source (excitation light source), 13 ... Rotating fluorescent plate (fluorescent disc), 14 ... Motor (motor part), 30B, 30G, 30R ... Liquid crystal light modulation device, 50 ... Second light source (solid light source), 55... Light source device, 60... Projection optical system, S1 to S8.

Claims (7)

A light source device including an excitation light source that emits at least excitation light;
A fluorescent disk in which the phosphor that converts the excitation light into fluorescence is continuously formed along the circumferential direction;
A motor unit for rotating the fluorescent disk in the circumferential direction around an axis passing through the center of a circle;
A light modulation device for generating image light by modulating light including at least the fluorescence;
A projection optical system for projecting the image light,
When the number of rotations of the fluorescent disk reaches a predetermined number lower than the target number, the excitation light source is turned on, and after the number of rotations of the fluorescent disk reaches the predetermined number, the number of rotations of the fluorescent disk increases. Then, the output of the excitation light source increases.   The projector according to claim 1, wherein the output increases as the input power to the excitation light source increases.   The output of the excitation light source is increased based on a lookup table in which a relationship between an elapsed time after the rotation number of the fluorescent disk reaches a predetermined number and a rotation number of the fluorescent disk is set in advance. The projector according to claim 1 or 2.   3. The projector according to claim 1, wherein the number of rotations of the fluorescent disk is detected from the motor unit, and the output of the excitation light source is increased according to the detection result.   The timing at which the number of rotations of the fluorescent disk reaches a target number is earlier than or substantially equal to the timing at which the input power to the excitation light source reaches a target value. 5. The projector according to any one of 4. Driving the excitation light source by pulse driving;
The projector according to any one of claims 1 to 5, wherein a driving frequency of the excitation light source is not less than three times a non-integer multiple of the frequency of the fluorescent disk. The light source device includes a solid light source that emits light that forms white light together with the fluorescence,
The projector according to claim 1, wherein the excitation light source is turned on and the solid light source is turned on.

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